Add command-line-value→suite mapping (for backports)
Add command-line-value→suite mapping (for backports)

The Release files on backports have Suite == Codename, e.g. both are
set to jessie-backports.

This makes URLs such as /stable-backports/i3 work in the redirector.

Debian/debiman,stapelberg/debiman,stapelberg/debiman